This is a follow up question to this question.

This question is not directly related to the MCAS system in the new B737 MAX aircraft, instead, my question is about the checklist for a runaway stab trim. What are the items on the Boeing B737 Max checklist to deal with a runaway stab trim? (Better yet, a picture of the actual checklist would be awesome!).

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    $\begingroup$ runaway stab trim is not very specific, this term seems to be applied more to the pilot's perception than the function itself. the good screenshot below specifies "continuously", where-as i would consider recent discussion to be about an "intermittent" function. $\endgroup$
    – Jason K.
    Commented Apr 21, 2019 at 19:58
  • $\begingroup$ To those commenting below about the incredible simplicity of the "proper" response to runaway stab trim: I congratulate you on your 20/20 hindsight. You see, you have the benefit of knowing what B had f'd up on MCAS. The real situation in the cockpit was, that very soon after T/O, pretty much all the bells and whistles were alerting the crew to a plethora of faults. As they did their best to figure out what the hell was wrong with the plane, they simply got overwhelmed. For those interested: knkt.dephub.go.id/knkt/ntsc_aviation/baru/… $\endgroup$
    – Jpe61
    Commented Oct 25, 2019 at 19:09

1 Answer 1


Here is a screenshot of a B737 Max 8 Runaway Stabilizer Checklist. There might be some small variations in the checklist when comparing each individual airline.

enter image description here

Additionally, here is the Boeing "Uncommanded Nose Down Stabilizer Trim" bulletin that was issued to all B737 Max 8 operators after the Lion Air crash.

enter image description here enter image description here

  • $\begingroup$ awesome! Perfect. Is it just me, or is this really straight forward. If you have unwanted nose down stabilizer trim (for whatever reason) flip stab trim to cutout and manually trim up. $\endgroup$
    – Devil07
    Commented Mar 22, 2019 at 0:03
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    $\begingroup$ It is really straight forward. So straight forward that the the deadheading pilot on the previous day's Lion Air flight managed to figure it out all on his own. MCAS was not common knowledge so you could excuse the Lion Air 610 pilots who then crashed the next day. But after the fact you would expect all B737 Max 8 pilots to be very familiar with MCAS and how to deal with any stab problems. $\endgroup$ Commented Mar 22, 2019 at 1:35
  • $\begingroup$ Keep in mind about the sanctimonious armchair quarterbacking over this, this can happen to ANY pilot. The Lion Air accident may well be filed under another case of otherwise smart people doing stupid things in airplanes and getting killed. The accident appears to be the culprit of negligent maintenance followed by poor aircrew handling. $\endgroup$ Commented Mar 22, 2019 at 12:27
  • $\begingroup$ @CarloFelicione I agree with your analysis in that this event like many accidents are caused by a chain of events, design deficiencies (MCAS relying only on a single AOA sensor), maintenance deficiencies (mechanics clearing the aircraft even after previous Lion Air crew experienced exact same issue), and pilot negligence (not recognizing trim wheels spinning forward as cause for nose down attitude). If any one of those links are broken, the accident is avoided. There is going to be enough blame to go around, but crew was last link in the chain, and could have easily avoided the disaster. $\endgroup$
    – Devil07
    Commented Mar 22, 2019 at 15:23
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    $\begingroup$ Its important to note that this checklist applies to trim movement that occurs continuously. In the MCAS accidents, the trim-movement happened intermittently (on a few seconds, off for period, on again). This checklist does not technically apply to the MCAS scenario. $\endgroup$
    – abelenky
    Commented Oct 25, 2019 at 15:20

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